THE “NO SCAR” METHOD
GENETIC TESTING IN THYROID CANCER
GOITER AND THYROID GLAND DISEASES
Goiter, is the name given to the enlargement, for various reasons, of the thyroid gland. The thyroid gland is a butterfly-shaped, hormone-producing organ located in the front of the neck. With the hormones it produces, the thyroid gland provides the body with energy almost like a battery. The over-production of thyroid hormones is called hyperthyroidism and the under-production of thyroid hormones is called hypothyroidism. While hyperthyroid patients experience symptoms like hyperactivity, palpitations, fast heart rate, weight loss despite an increase in appetite, nervousness, trembling and sweating, hypothyroid patients often complain of symptoms such as sluggishness, weight gain, water retention, dry skin and constipation. Besides these functional disorders of the thyroid gland, there are also some structural abnormalities. Diseases characterized by a partial or complete enlargement of the thyroid gland are called nodular goiters. Various diseases of the thyroid gland can be seen in approximately 40% of the population in Turkey, which means around 20-30 million people are affected. There are a number of factors which play a role in goiter formation, the main ones being:
1. Iodine deficiency and other environmental factors
2. Hereditary factors
3. Constitutional factors
Of these factors, the significance of iodine deficiency must be emphasized. Research shows that people in Turkey only meet around a quarter of the recommended daily intake of iodine. In Central European countries, iodine deficiency and the goiter problem associated with it has been resolved to a great extent by adding iodine to bread and table salt. This is an important issue for Turkey, thus people without goiter need to increase their intake of iodine as a preventive measure. On the other hand, people with goiter should avoid iodine intake as it can cause more harm than good.
Thyroid nodules have been detected more frequently particularly owing to the increased use of neck ultrasounds. If a nodule is detected on the ultrasound of a patient, a scintigraphy is performed which provides a functional map of the thyroid gland. This shows us whether the nodules are functional or not. Nodules which are not functional are called cold nodules and carry a higher risk of malignancy. While 5-15% of nodules are cancerous, in order to avoid unnecessary surgery on cancer-phobic patients, a procedure known as a Fine Needle Aspiration Biopsy (FNAB) is carried out. This has a sensitivity rate of 95% in the diagnosis of thyroid cancer. As a result, patients with benign nodules can be given thyroid hormones and monitored safely until an ultrasound shows an enlargement of the nodules. However, it must be stressed that although an FNAB is 95% accurate, there is still a 5% false-negative rate.
It is important to test a patient for possible cancer prior to surgery for the following reason. If a certain amount of thyroid tissue is left remaining in the gland and the removed tissue shows malignancy, the patient will have to undergo a second operation to remove the remaining thyroid gland. Since a second operation is relatively more difficult to perform, we as surgeons prefer to do whatever is necessary in the first operation.
In addition to all this, it is also necessary to emphasize that the majority of thyroid cancers are non- aggressive. In the USA, the probability of a patient dying of thyroid cancer is the same as the probability of a patient surviving by-pass surgery. In Turkey, the chances of someone dying in a car accident are higher.
One remarkable development in thyroid cancer in recent years has been the genetic testing of the blood to determine whether a parent with medullary thyroid cancer has passed this disease onto the child. A child who tests positive is very prone to developing the disease by the age of 25- 30, in which case the child's thyroid gland can be completely removed as a curative measure. This is considered as one of the most important contributions that genetics has made to the field of medical practice. We have many patients and families in this situation; however, it is rather difficult to persuade mothers to go ahead with the surgery when their child has not yet developed the disease.
An important difference between thyroid operations and other operations is the need for a group of specialists to work together closely since thyroid gland diseases cannot be treated by the surgeon alone. It is necessary for the endocrinologist, nuclear medicine specialist, pathologist, radiologist and surgeon to work as a team to evaluate each patient and decide on the best method of treatment.
FREQUENTLY ASKED QUESTIONS ABOUT THE THYROID
What is a thyroid gland? What is its function? What are the symptoms of thyroid disease?
The thyroid is a gland located right in front of the windpipe. It secretes thyroid hormones which regulate the function of virtually the whole system and organs of the body, from the nervous system to the digestive system. The name given to the branch of science dealing with diseases of the thyroid gland is ‘endocrinology' and the name given to the surgery of the thyroid gland is ‘endocrine surgery'.
The enlargement of the thyroid gland is called goiter. Nowadays, it is rare to see patients seek medical help for large swellings of the neck, as was the case in the 1960s. Instead, thyroid nodules are generally being detected on an ultrasound or coincidentally during a physical examination. In addition to this, there are also hormonal disorders associated with the thyroid.
How are hormonal disorders of the thyroid detected?
An uncontrolled increase in the secretion of hormones from the thyroid gland, known as hyperthyroidism, causes weight loss (despite an increase in appetite) in young patients and palpitations, trembling hands, sweating, heat intolerance, nervousness, irregular menstrual patterns, hair loss and diarrhea in older patients. The more commonly seen hypothyroidism, which is the insufficient secretion of hormones, causes swelling of the face and body, water retention, weight gain, constipation, irregular menstrual patterns, hair loss, dry skin, cold intolerance, a decrease in physical activity, and in the later stages, a decrease in mental activity.
What is the incidence of thyroid diseases in Turkey?
Varying sizes of thyroid nodules can be seen in 40% of the population and in 60% of women. While 95% of these nodules are benign, 5% show malignancy. Due to the rapid increase in thyroid inflammation in recent years, hypothyroidism – which is more commonly seen than hyperthyroidism – now affects about 20% of women aged around 40.
What causes inflammation of the thyroid?
The addition of iodine to our table salt has been a major step in protecting future generations from developing goiter. However, as in all countries where this is implemented (Argentina, Sweden), the risk of developing inflammation of the thyroid (also known as thyroiditis) and a special form of this called Hashimoto's Thyroiditis ,which can also lead to thyroid cancer, increases 4-5 fold. For this reason, it is better to give babies and children in the developing stages iodized salt and it is better for adults, especially thyroid patients, to avoid using it. Food should be cooked without salt and there should be two salt shakers on the table: one with iodized salt for children and one without for adults.
What should be done for the early detection of thyroid disease?
All check-up programs should include the measurement of the TSH hormone - the most sensitive indicator of thyroid hormone levels - and a thyroid ultrasound. Thyroid ultrasounds and fine needle aspiration biopsies should also be included in public health screenings, just as a mammogram for breast cancer and a smear test for cervical cancer is.
What are the latest thyroid cancer statistics?
Paul W. Ladenson, President of the American Thyroid Association, announced that the theme of his presidential year would be “Thyroid Cancer 2005” . Some thyroid cancer statistics published in “Thyroid” (April 2005) illustrate why:
• Over 25,000 people in the USA will be diagnosed with thyroid cancer by the end of 2005. This is twice the number of patients 15 years ago.
• Thyroid cancer, which was the 14th. most common cancer in the 1990s, has now climbed to 7th. place.
• Thyroid cancer has been the most rapidly increasing among all cancers, with an annual increase of about 4% in women and 2% in men.
• Despite being more commonly observed in women, thyroid cancer has shown the biggest increase as a death-causing cancer among men
Thyroid cancer in relation to the Chernobyl disaster has been much talked about. Can the effects still be seen?
The radioactive iodine which was emitted in the Chernobyl disaster, greatly affected, in particular, the thyroid and children in the developing stages. As the dose of radioactive iodine was very high, the cancer emerged within 4-5 years. Fortunately, with intense screening efforts, thousands of children have been diagnosed in the early stages and saved with surgery. However, if we were now to come across a thyroid cancer patient who was living in the region at the time of the exposure, we would not be able to determine whether this disease was acquired then or whether it emerged later on.
What kind of diagnostic tools are used in thyroid patients?
In the past, thyroid patients were diagnosed with a measurement of thyroid hormones and a thyroid scintigraphy. Today, however, a scintigraphy is used to show whether the thyroid is under-functioning or over-functioning. For nodules and thyroid cancer, we prefer to use the more sensitive ultrasonography.
What can be done to determine whether a mass in the thyroid is benign or malignant?
We perform a fine needle biopsy on the mass, which is then evaluated by an experienced pathologist. If the result is benign, it is 95% accurate. If it is malignant, it is 99% accurate. For this reason, we recommend that surgery is not carried out without performing a fine needle biopsy first, so that the surgeon does not face any unexpected post-operative surprises – especially if the surgeon has little experience.
Can patients with a negative fine needle biopsy be followed?
Despite a small risk, a patient can be safely followed. If the nodule continues to grow and becomes so big that it starts to press against other structures in the neck, it can always be surgically removed. However, the aim of the endocrine surgeon should be to detect the hidden malignant nodules, not the benign ones.
How is surgical treatment of thyroid nodules or thyroid cancer carried out?
The treatment of thyroid diseases requires complete team work. The endocrine surgeon, nuclear medicine specialist, radiologist and pathologist can reach the best decisions only by working in close contact with one another. The complexity of thyroid diseases requires a substantial amount of time and attention on the part of all the specialists involved. This is necessary in order to fully concentrate on the patient.
Thyroid surgery, on the other hand, is like embroidery. That is, it requires delicacy, precision and meticulous skill. It is particularly important to take extreme care when dealing with the vocal cords and neighboring parathyroid glands. The risk of the disease recurring after surgery also has to be reduced to a near 0%. Since 2004, with the aid of the latest technological devices, thyroid surgery has been carried out using the minimal access approach method, which involves a 2.5-cm incision to the side of the neck, as opposed to the traditional method of making a long incision along the base of the neck. This method is particularly preferred by women, and also men, in terms of both cosmetic appearance and decreased post-operative discomfort.
What is radioactive iodine treatment and who is it used for?
Radioactive iodine – also known as radioiodine - is administered in small doses to treat hyperthyroidism and in large doses to treat thyroid cancer in addition to surgery. It is also used in the treatment of distant metastasis. The radioactive iodine used for this treatment is the same as that emitted in the Chernobyl disaster.
Are all hyperthyroid patients given radioiodine treatment?
Different countries have different attitudes with regard to who should be given radioiodine treatment. For example, the USA commonly uses radioiodine treatment for all kinds of hyperthyroidism and across all ages. The UK, on the other hand, prefers to use medical treatment lasting between 1-1.5 years in an attempt to lower hormone levels. In Turkey, both treatment methods are used. However, surgery is also recommended if the patient has an enlarged goiter, a suspicious nodule, or cannot take medication for one reason or another.
Is a patient's preference considered in the treatment of hyperthyroidism?
Sometimes patients who are planning a pregnancy do not want to waste time with medication or do not want to defer pregnancy following radioiodine treatment. Thus, they prefer to undergo surgery. On the other hand, some patients - after having gone through all treatment options available to them - may prefer radioiodine treatment or medical treatment.
Are there any restrictions following radioiodine treatment?
This can vary from country to country depending on the radiation safety legislation. In our country, patients can go home after radioiodine treatment if the dose they are given is under a certain level. However, they are advised to avoid contact with babies for a week. On the other hand, a patient who has received radioiodine treatment for thyroid cancer is kept in an isolated room for five days to avoid exposing their family members to radiation. Patients usually see this as a kind of quarantine but there are certain hospitals which have rooms with all amenities, enabling patients to get through this period in comfort. Contact with babies is also restricted after this treatment.
In which type of thyroid disease are the eyes affected?
The bulging of the eyes and retraction of the eyelids is observed in a special form of hyperthyroidism called Basedow-Graves Disease. The successful treatment of hyperthyroidism also has a positive impact on the eyes. However, in some patients these eye conditions may remain unchanged or continue to progress, in which case further investigations into the eye may be necessary.
Which patients receive surgical treatment?
Surgical treatment is carried out on three different groups of patients. The first group consists of patients who have been diagnosed with thyroid cancer through a fine needle biopsy or those whose biopsy results read suspicious for thyroid cancer. The second group consists of patients with nodules that are considered benign but continue to grow until they start to press against other structures in the neck. The third group consists of patients whose hyperthyroidism cannot be controlled with medication or radioiodine treatment.
What procedure is followed in the surgical treatment of hyperthyroid patients?
There are two main aims in the surgical treatment of hyperthyroidism; to eliminate the disease and to prevent its recurrence. For this reason, if we are to perform surgery on a patient with Basedow-Graves Disease (which also affects the eyes and is more commonly seen in younger age groups), 95% of the thyroid must be removed. This means that the patient will need to take thyroid hormones for the rest of his or her life. However, if insufficient thyroid tissue is removed, hyperthyroidism may persist or recur. Preserving a large amount of thyroid tissue so as not to put the patient on medication, will only result in failure and may require a second operation.
What kind of treatment is given to patients with a growing but benign nodule?
If the fine needle biopsy results for these patients read benign prior to surgery, it is a general surgical principle to completely remove the side of the gland with the nodule. If the other side of the gland is healthy and the patient is over 50, there is no harm in preserving the remaining gland as the risk of developing goiter after this age decreases. However, the high level of iodine deficiency and the growing number of coincidental thyroid cancers in our country, has led us in recent years to opt for the complete removal of the thyroid.
What should be done if thyroid cancer is detected before or during surgery?
Thyroid cancer treatment begins with surgery and this means the complete removal of the thyroid. If less than 95% of the thyroid is removed, the effectiveness of radioactive iodine treatment decreases, which in turn will necessitate a second operation prior to starting the treatment. During surgery, it is 90% possible for experienced surgeons to detect thyroid cancer with the bare eye. However, in suspicious cases or small foci areas, a pathologist is called into the operating room to freeze and evaluate the tissue.
Why is thyroid surgery complicated?
The treatment of thyroid diseases requires complete team work. The endocrine surgeon, nuclear medicine specialist, radiologist and pathologist can reach the best decisions only by working in close contact with one another. The complexity of thyroid diseases requires a substantial amount of time and attention on the part of all the specialists involved. This is necessary in order to fully concentrate on the patient. Thyroid surgery, on the other hand, is like embroidery. That is, it requires delicacy, precision and meticulous skill. It is particularly important to take extreme care when dealing with the vocal cords and neighboring parathyroid glands. The risk of the disease recurring after surgery also has to be reduced to a near 0%.
Can thyroid operations be performed using the video-assisted technique?
Since 2004, with the aid of the latest technological devices, thyroid surgery has been carried out using the minimal access method, which involves a 2.5-cm incision to the side of the neck, as opposed to the traditional method of making a long incision along the base of the neck. This method is particularly preferred by women, and also men, in terms of both cosmetic appearance and decreased post-operative discomfort. However, in these operations, a pathologist must be present in the operating room to evaluate the tissue so that the thyroid can be completely removed if necessary. (See Surgical Techniques page)
How long are patients kept in hospital?
Patients who have undergone minimal approach surgery can go home the same day. Patients who have been operated on using the classical method, stay in hospital overnight and are discharged within 24 hours. A patient who takes thyroid hormone replacement medication functions no differently to a person with a healthy thyroid.